A new study shows that fetal exposure to ordinary electromagnetic fields increases a child's risk of asthma.
A new study shows that fetal exposure to ordinary electromagnetic fields increases a child's risk of asthma.
The XX Factor
What Women Really Think
Aug. 2 2011 11:57 AM

The Blow Dryer v. the Fetus

Photo illustration by Daniel Berehulak/Getty Images

The same researchers who first found a link between exposure to low-frequency electromagnetic fields (EMFs: ordinary magnetic fields generated by "pretty much anything that uses electricity") and miscarriage have extended their research and found that the higher the exposure in utero, the greater a child's risk of asthma years later. Dr. De-Kun Li, a reproductive and perinatal epidemiologist at Kaiser Permanente Division of Research, followed up with the women who first wore monitors during their pregnancies years ago. The women were unable to see their own levels of exposure, and recorded for researchers nothing more than basic information about their daily whereabouts: at home and not in bed, at home in bed, at work, traveling and other.

Li's team found little difference in EMF levels at any location, but still attributed the most exposure to common household appliances (for unexplained reasons) and suggested that women try to limit their exposure. Here's the helpful quote from the Time magazine article on the research: "Don't stand in front of the microwave when it's heating food, for example, and hold the hair dryer as far away from your belly as possible, or switch to a dryer that's battery operated."


I appreciate that Li offers an explanation for the association. "The latest research suggests that cells use magnetic fields to communicate with each other. If an external EMF comes into interfere with that, cell communication needed for normal development can be disrupted." But if I were pregnant, it's that explanation that would give me the most pause. Li's research specifically didn't consider higher-frequency electromagnetic fields, such as those generated by mobile phones and wireless networks. A hair dryer is easy to avoid; a wireless network nearly impossible (particularly if a woman wishes to remain employed). Asthma isn't the worst diagnosis in the world, and a "greater risk" of it in one's teens is scarcely cause for alarm. It's less the actual result of this particular reseach that caught my attention than the general direction in which it seems to be heading, toward yet another portrait of the world as hostile to pregnant women and the children they carry.

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